idle valve

Posted: Wed Jul 27, 2011 5:07 pm

Hi everyone, i have replaced the idle valve week ago with aftermarket one from ebay as the old one was causing stalling or not starting when warm. Everything runs fine now but- when i press accelerator, rpm goes up but when i let go off the pedal they also stay up for like 2seconds before they drop. also the engine keeps rpm quite high on idle like 1000 but 2 days ago they been on like 1600rpm. i have moved the valve up and down and tried to loosen a accelerator cable a bit.seemed ok now but still not sure about rpm staying up too long. seems like either valve or the cable is not releasing as it should. any ideas?

Posted: Thu Jul 28, 2011 2:43 pm

was the valve new.

How do you know that the aftermarket part is the right one for your car

Posted: Fri Jul 29, 2011 8:21 am

Hi mike,

i have checked the part number against mine original one. it was matching. Also confirmed with seller. and once i had the part i compared it with mine and it was as well matching.only difference is that new one is chrome and old one was black. And yeah it was brand new not a sign of previuos use. it was like 50 quid and normally they are much more i think, so im wondering. i will post picture. the car starts and runs fine and revs are not as erratic and no sign of cutting out when warm at all. here is a link. its the very first one on the list form company called air flow meter company
http://www.google.co.uk/search?q=audi+coupe+2.0+16v+idle+valve&hl=en&tbm=shop&aq=f&oq=&aq=f

do you reckon i should loosen a accelerator wire bit more? its very tight and not releasing properly.
any info will help please
thank you so much

Posted: Fri Jul 29, 2011 1:25 pm

I'd suspect there may be another fault.

The throttle cable shouldn't be tight and they can be adjusted.

Posted: Sat Jul 30, 2011 12:26 pm

[quote="Mikes2"]I'd suspect there may be another fault.

The throttle cable shouldn't be tight and they can be adjusted.[/quote

Hi Mikey,
Last night i've adjusted the throttle cable.cleaned it all and put bit of lubricant on. bit better but still. what i think there is like a little spring on throttle body which should bring the cable back once you let go off throttle and that seems to have a bit of resistance maybe a 2-3mm before it returns completely. so definetely not the idle valve. Do you now it that can be fixed without changing the whole throttle body/? cheers

Posted: Sat Jul 30, 2011 9:13 pm

try cleaning it out - the butterflies may be sticking with carbon build up

Posted: Sat Jul 30, 2011 10:19 pm

haha cheers will do.that wont help do you think i could just get another spring or make one up?

Posted: Mon Aug 01, 2011 4:52 pm

gave it good clean and bit of lubricant but still keeping revs high for second or two. Question

Posted: Mon Aug 01, 2011 5:00 pm

check all your vac pipes

Posted: Mon Aug 01, 2011 6:35 pm

check all your vac pipes

Posted: Sat Aug 06, 2011 8:35 am

mmmm checked but nothing. everything seems ok. will take off throttle body today and give it a proper clean. let you guys know how i got on.. Cool

Posted: Sat Aug 06, 2011 11:25 am

i had a similar thing and the pipe that runs to the air box was split right at its connecting point Rolling Eyes

Posted: Sat Aug 06, 2011 12:24 pm

alrite i will take off whole thing and check it properly... Rolling Eyes

Posted: Fri Aug 12, 2011 3:22 pm

new iddle valve

Posted: Wed Sep 14, 2011 12:14 pm

right so after about 2 months having no succes of finding why the hell i my revs are staying up for couple seconds after releasing pedal it start to ease off by itself so it makes me thing that brand new aftermarket idle valve would be too reason and needed some time to run in?

Needs to get out more Joined: Jun 21, 2009 Posts: 161

1st thing i would put a jubile clip on the idel valve ar listen for vacumm leaks.
2nd does it have throttle damper on it its on the bottom of the throttle butterflies.

Posted: Thu Sep 15, 2011 2:30 pm

yeah it does man. why?

Needs to get out more Joined: Jun 21, 2009 Posts: 161

some times the damper can be slow returning try taken it of see if it makes any diffrence

Posted: Thu Sep 22, 2011 6:03 pm

yeah it seems bit stiff. i have cleaned it already and put bit of lubricant on it. it helped a bit but the revs stays on like 1100rpm on idle.before it was like 900 and throtle was much more responsive on foot. im changing the rocker gasket so will take everything off and see what i find. cheers mate

Newbie Joined: Jul 12, 2010 Posts: 15

Well been watching this thread for last couple of weeks as my coupe seems to be having the same sort of symtoms. The revs seem to be holding up as change gear or depressing the clutch. Now done all the above as changed the temp switch, isv cleaned out throttle body, checked for vacuum leads etc,etc. Now to me it seems temperture related. Shot in the dark but the temp sender that just hangs in mid air, is that just for the cooling fans?

Posted: Fri Sep 23, 2011 6:23 pm

did you also changed idle valve? cos my troubles started immediately after new valve was fitted. Which switch do you mean exectly? the one for fans is connected at the bottom of radiator. that has nothing to do with idle valve. im getting rocker gasket changed probably next weekend so whole metering head and throtle body as well as inlet manifold will be removed so will have a better look then. let me know if you make any progres pls mate

Needs to get out more Joined: Dec 03, 2010 Posts: 178

andym, the temp sensor that hangs mid air, if its the one im thinking of that is bolted to the bracket on the side of the head/block, it is for the cooling fans after run when the ignition is switched off and the engine is very hot, think it is something to do with air con and turbos for different engines.
cant see it being related to your idle /rev problems. try the damper that was mentioned??

Newbie Joined: Jul 12, 2010 Posts: 15

Well without tempting fate, i think ive cured mine. We replaced the ISV again as not totally happy with the last one. Made abit of improvement but not still not right. Took car to local VAG specicalist who pluged the car into his vagcom and cleared the faults that were logged. With its memory wiped clean its as good as gold now. Worth a try LUIGI.

Posted: Wed Oct 05, 2011 9:26 pm

ok will take try that but i have strange feeling as when i dsconnect idle valve it does not do a thing, now shouldnt this cause the engine running different? will take it to shop and see what happens.how much did you pay for this?.thanks for post andy

Posted: Fri Oct 07, 2011 8:17 pm

Just scanned this thread. Have you checked the intake boot for splits?? Is it the 16v you have, can't mind what they are like but the boots with the crankcase return below are bad for splitting. Sounds like you have another problem to me.

I think if you pull the plug on the ISV when it is running it will do little difference, however would be different if you started it with it disconnected.

Newbie Joined: Jul 12, 2010 Posts: 15

well must admit its 98% better, but some days it seems to go better than others. Not sure it maybe just me. Must admit i tend to thing your right but ive checked all the pipe work and blowed if i can find a leak. Yes its a 16v and which one do you mean by return hose? Is that the one that goes along the n/s of the block under the inlet manifold and goes on to that housing on the block

Inexperienced Joined: Jun 10, 2010 Posts: 25

There are lots of cheaply made Idle Control Valves on the market, mainly on ebay. Mine was playing up after 15 years of use, instead of buying a new genuine Audi one for £100, I bought 3 from e-bay over a period of a month and all were rubbish and didn't cure the problem.
Bought one from Audi dealer - problem solved.
Cheap aftermarket parts can be okay for certain applications, but only use genuine parts if you want reliability on your engine.

Replacing an engine component with a cheap one from ebay wont mean that you have fitted a working part. Been there, done it myself.

Posted: Wed Nov 02, 2011 10:19 pm

right after hitting dead ends and stabbing in the dark i contacted company i bought the idle valve from as it is in warranty so they send me replacement valve with paper reading- new idle valve must be restarted as following; after new iac is fitted turn ignition on ( Do not start engine), leave for 1 seconds and switch off, repeat 3 times then start and drive on.
Does this make any sense to you folks? I will have a crack on this tomorrow morning and see what happens as the previous valve did not have those instruction... Rolling Eyes

Posted: Wed Nov 02, 2011 11:07 pm

Are they winding you up. The idle valve only works when the engine is running so what difference does it make how many times the ignition is on before you start it.

if it doesn't work first time, it will never work

I'd suggest a genuine part

Needs to get out more Joined: Dec 03, 2010 Posts: 178

i know on my 80 b4 2.0 that the icv is activated once the ignition is turn on and you can hear it and feel it humming without the engine running, but i agree swicthing the ignition on and off cant be doing much.